4.88's 35's and 6spd MPG's?
01-05-2011, 05:07 PM
#11
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6spd Manual Gearing
P.S. - I'm contemplating 4.56s too.
01-05-2011, 05:37 PM
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01-05-2011, 06:00 PM
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JK Jedi Master
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The issue is that for a very long time, 4.56's simply were not available. Your favorite websites may have 'listed' them, but had none in stock, could not find any, etc. So the choice was either 4.10's or 4.88's. If you can find some 4.56's now, great. If not, guess what?
01-05-2011, 07:38 PM
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So here is a question for anyone that would know the answer. When looking at the chart for gear changes in the FAQ section, are the RPM's posted supposed to be what you would see at 70 mph in 6th gear or overdrive for the autos or is it the RPM's when the transmission is at a 1:1 ratio. The reason I ask is that I have read where some say on a 6 speed, 1:1 is 5th gear. Does anyone know the answer to this? If the RPM's stated are while the trans is in 5th gear, then you would be a hundred or so lower in 6th gear and it would seem to make the chart somewhat misleading.
Last edited by BearInTheWoods; 01-05-2011 at 07:40 PM.
01-05-2011, 09:42 PM
#16
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Unless all your highway driving is in the 55-65 MPH range, there is no way I would go with 4.88's if I were you. In my opinion the RPM's would be too high all the time for any faster. I'm running 4.88's in my 6spd with 35's that actually measure about 34's and for highway driving I wish I went with 4.56's
sry bout typos
01-06-2011, 01:30 AM
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01-06-2011, 11:58 AM
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Im currently running 4.10's with 35" km2's and I am getting 14.9 mpg consistantly. I have a set of 4.88's sitting on the garage shelf waiting to go in. I have decided that when I put the 4.88's in that I am moving up to 37's. That will put my RPM's back to around 2400 at 70 mph. which is almost the same as stock 4.10's and 32's.
9mpg seems kind of low. I'm thinking a superchips to help calibrate the changes of tires and gears would have made a big difference.
9mpg seems kind of low. I'm thinking a superchips to help calibrate the changes of tires and gears would have made a big difference.
01-06-2011, 11:59 AM
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